Thermal extraction using radiation

Abstract

In one embodiment of the present disclosure, a device is disclosed comprising a macroscopic thermal body and an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body. The macroscopic thermal body having a thermal emitting area, and the extraction structure configured and arranged to facilitate emission from, or receipt to the thermal emitting area that exceeds a theoretical, Stefan-Boltzmann, emission limit for a blackbody having the same thermal emitting area as the thermal body.

What is claimed is: 
     
       1. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the extraction structure is configured and arranged to
 provide sufficient radiation channels over the thermal emitting area to increase a number of internal modes of the thermal emitting area that couple to the external medium, or 
 have an electromagnetic density of states that is at least equal to that of the thermal emitting area; and 
 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area. 
 
     
     
       2. The device of  claim 1 , wherein the macroscopic thermal body has internal electromagnetic density of states that is greater than internal electromagnetic density of states of a vacuum. 
     
     
       3. The device of  claim 1 , wherein the extraction structure is configured and arranged with an index of refraction that is greater than that of air and to pass the emission between the thermal body and the external medium. 
     
     
       4. The device of  claim 1 , wherein the extraction structure is configured and arranged to provide enough radiation channels over the thermal emitting area to increase the number of internal modes of the thermal emitting area that couple to the external medium. 
     
     
       5. The device of  claim 1 , wherein the extraction structure is configured and arranged to have the electromagnetic density of states that is at least equal to that of the thermal emitting area. 
     
     
       6. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, wherein the extraction structure is a hemisphere-shaped structure with a radius (R) and an index of reflection (n e ) and is configured and arranged to provide accessibility to a far-field medium for optical modes that couple radiation with the thermal emitting area, and the macroscopic thermal body is a disk shaped-structure with a radius (r). 
 
     
     
       7. The device of  claim 6 , wherein the extraction structure is configured and arranged to provide the accessibility by way of constraints on a geometry of the extraction medium, and wherein the extraction structure and the macroscopic thermal body are arranged such that R is greater than or equal to n e r. 
     
     
       8. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, the extraction structure is configured to absorb a fraction of the emission, the macroscopic thermal body is formed by an open area of an absorptive cavity, and the extraction structure is a semi-spherical dome configured and arranged at an entrance of the absorptive cavity. 
 
     
     
       9. The device of  claim 8 , wherein the device is configured to cool a heat source using a heat capacity of the extraction structure, wherein the extraction structure is a focusing lens shaped as the semi-spherical dome. 
     
     
       10. The device of  claim 8 , wherein the device is configured to cool a heat source, including circuitry, by absorption of radiation in the extraction structure, combined with conduction of heat away from a surface of the extraction structure. 
     
     
       11. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, the extraction structure is configured and arranged to absorb a fraction of the emission and to cool a heat source using a heat capacity of the extraction structure by absorption of the emission in the extraction structure combined with conduction of heat away from the thermal emitting area. 
 
     
     
       12. The device of  claim 1 , wherein the extraction structure is configured and arranged to be close enough to the macroscopic thermal body to allow for photon tunneling between the macroscopic thermal body and the extraction structure. 
     
     
       13. The device of  claim 12 , wherein a distance between the extraction structure and the macroscopic thermal body is less than a wavelength of emitted or received thermal energy. 
     
     
       14. The device of  claim 12 , wherein the extraction structure does not contact the macroscopic thermal body. 
     
     
       15. The device of  claim 14 , wherein the extraction structure is configured to be maintained at a temperature independent of a temperature for the macroscopic thermal body. 
     
     
       16. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, wherein the emission from or receipt to the thermal emitting area exceeds the Stefan-Boltzmann emission limit for a blackbody having the same thermal emitting area as the thermal body by a factor of at least 3. 
 
     
     
       17. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, wherein the extraction structure is configured and arranged to facilitate the emission level from or to the thermal emitting area by increasing radiation coupling with the thermal body to an emission level beyond the Stefan-Boltzmann emission limit, through the extraction structure and with the external medium via far-field radiation. 
 
     
     
       18. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, wherein the extraction structure is configured and arranged to transfer radiation between the thermal body and the external medium utilizing far-field radiation while enhancing radiation coupling with the thermal body beyond the Stefan-Boltzmann emission limit. 
 
     
     
       19. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate a level of emission from or to the thermal emitting area; 
 wherein the level of emissions facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, without photon tunneling. 
 
     
     
       20. A device manifesting a level of emission from or to a thermal emitting area as measured relative to a blackbody having a theoretical thermal emitting area, the thermal emitting area and the theoretical thermal emitting area characterized by a common geometric cross-sectional area, the device comprising:
 a macroscopic thermal body having the thermal emitting area; and 
 an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body and configured and arranged to facilitate the level of emission with an external medium from or to the thermal emitting area; 
 wherein the level of emission facilitated by the extraction structure exceeds a theoretical, Stefan-Boltzmann emission limit for the blackbody having the theoretical thermal emitting area with the common geometric cross-sectional area, wherein the extraction structure is configured and arranged to facilitate the level emission from or to the thermal emitting area by increasing an amount of radiation emissions coupled with the thermal body to a level of radiation emissions that exceeds the Stefan-Boltzmann limit, and wherein the extraction structure is configured and arranged to have an electromagnetic density of states that is greater than that of the thermal emitting area.